Google held a 70.95% share of the search market in February, according to Hitwise. In recent months Google has maintained its wide lead, with search market share totals ranging from a low of 70.60% last October to a high of 72.25% in December.

Microsoft Bing, which held third place behind Google and new partner Yahoo Inc. last month, has been moving in the right direction, rising from 8.92% of the search market in December to 9.37% in January and improving again to 9.70% last month.

Ezra Gottheil, an analyst at Technology Business Research, isn't surprised that Bing has been slow to make its mark in a market so dominated by Google.

"Even if [Bing] is getting traction, growth would be slow," Gottheil said. "People don't change without some impetus. Google isn't broken. Why fix it? At best, it's going to be a long road for Microsoft."

On the other hand, Gottheil noted that Bing isn't doing badly for a relatively new product -- "9.7% of a huge business is a large business," he said.

Meanwhile, Yahoo has been seeing a fairly steady decline since last September, according to Hitwise. While Yahoo did manage to hold firm at 14.57% of the market in both January and February, its share is down from 16.38% six months ago.

Gottheil noted that Yahoo's decline, while steady, has not been especially sharp. "A couple of points probably doesn't mean that much, [so] there's no reason for anyone -- Google, Bing, or Yahoo users -- to change."

Microsoft over the past year has been spending a lot of money and development resources to capture some of Google's hefty share of the search market.

Its latest move -- signing a deal to have the Bing search engine power multiple Yahoo sites -- could prove the most significant so far. That deal was approved last month by both the U.S. Department of Justice and the European Commission.

The partnership also calls for Yahoo to sell premium search advertising services for both companies.